T A N E 29, 1983

C O M M O N L I C H E N S OF A U C K L A N D CITY

by Bruce W. Hayward* and Glenys C. Hayward! * New Zealand Geological Survey, P. O. Box 30368, Lower Hutt

t 35 Trafalgar Street, Lower Hutt

S U M M A R Y

Lichens are a major, although much neglected, part of the flora of Auckland city and suburbs. They grow in profusion on soil, clay banks, rocks of the volcanic cones, trees in gardens and parks and especially on man-made features such as fences, tile roofs, brick chimneys, concrete walls and tarsealed roads.

The lichens most frequently encountered in Auckland are Xanthoparmelia scabrosa, Dirinaria picta, Parmotrema perlatum, Ramalina linearis and Xanthoria parietina. These and most of the other common lichens of the city and suburbs are described and illustrated.

INTRODUCTION

Lichens are a prominent part of the flora of Auckland city and suburbs, not only on soil and clay banks, on rocks of the numerous, small, volcanic cones, on the bark of trees found in most gardens and parks, but particularly on man-made structures such as wooden fences, power poles, brick chimneys, tile roofs, tarsealed roads, stone curbs and even rarely glass windows, corrugated iron and discarded clothing. Despite their abundance there has been no previous work on the city's lichens.

Lichens are a unique group of plants. Each is composed of a microscopic green or blue-green alga living in a symbiotic association with a filamentous fungus. Together they form a new plant body, the lichen thallus, which is quite unlike an alga or fungus growing alone.

Lichens are often confused with mosses, liverworts and fungi. They are not differentiated into leaves and stems like mosses and liverworts and lack their sporophyte capsules. Free-living fungi lack the green or blue-green internal layer of algae, that is so obvious in lichens when they are wet.

Lichen identification Here we have attempted to discriminate the chosen lichens using

features visible to the naked eye or with no more than a 10 X hand lens. It should be appreciated however, that the identification of many lichen genera and species require more complicated chemical or microscopical techniques, not described here.

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Fig. 1. Common fruticose (a-d) and foliose a. Cladonia leptoclada (4); c. Teloschistes chrysophthalmus (7); e. Dirinaria picta (9), 6 cm diameter; g. Neofuscelia verrucella (13); Scales with 1 mm divisions; coin 17 mm

(e-h) lichens of Auckland. b. Ramalina linearis (5), 8 cm across; d. Usnea sp. (8); f. Leptogium sp. (12); h. Parmotrema perlatum (16).

diameter.

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Fig. 2. Common foliose (a-d) and crustose (e-h) lichens of Auckland. a. Pseudocyphellaria aurata (18), wet; b. Pseudoparmelia caperata (22); c. Xanthoparmelia australasica (24); d. Xanthoria parietina (26); e. Lecidea sp. (27); f. Lecanora atra (28); g. Phaeographis australiensis (31); h. Thelotrema lepadinum (32). Scales with 1 mm divisions; coin 17 mm diameter.

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The colour of the dry thallus is often a significant feature. When it is wet the upper cortex (Fig. 3) often becomes transparent and the colour

fruticose foliose crustose

Fig. 3. Cross-sections through the thalli of the three main types of lichen growth form, showing the basic differences in arrangement of the layers, a = algae confined to this layer; c = cortex; m = medulla.

of the alga (green or blue-green) shows through vividly, obscuring the colour.

G L O S S A R Y OF M O R P H O L O G I C A L T E R M S U S E D

apothecia - globose, disc- or cup-shaped fruiting bodies (1-20 mm in diameter); generally occur on the upper surface or margins of thallus (Fig. 4).

Fig. 4. Cross-sections through the thallus and apothecia of hypothetical lichens showing the differences between cyphellae and pseudocyphellae and between lecideine and lecanorine apothecia.

cephalodia - wart-like structures usually containing blue-green algae and growing on the surface of thalli with green algae,

cilia - hair-like structures on the margins or upper surface of lobes, apothecia or isidia.

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cortex - outermost layer of lichen thallus (Fig. 3), composed of fungal threads.

cyphallae - circular holes in the lower cortex of the foliose lichen Sticta; holes have raised rims and thin internal linings (Fig. 4).

isidia - finger-like, cylindrical or flattened outgrowths of the upper cortex; usually less than 2 mm long; may break off to become vegetative propagules.

lecanorine apothecia - apothecia surrounded by a thalline margin (Fig. 4).

lecideine apothecia - apothecia lacking a thalline margin (Fig. 4). lobe - rounded or strap-shaped portion of a foliose thallus, medulla - innermost layer of thallus (Fig. 3), composed of interwoven

fungal threads. phyllocladia - tiny granular or finger-like structures on branches of

Stereocaulon, pseudocyphellae - circular holes in the cortex through which fungal

threads of the medulla protrude (Fig. 4). rhizines - strands of fungal threads on the lower surface of many foliose

thalli; often attach lichen to substrate (Fig. 4). soralia - small compact masses of soredia on surface or margins of

thallus. soredia - minute clump of algal cells and fungal threads, without a

cortex, that erupts on the thallus surface as a powder; may be released as a vegetative propagule.

squamule - small, scale-like thallus segment, with an upper cortex but no lower cortex.

thallus - entire lichen, other than its fruiting bodies, tomentum - a thin mat of felty hairs on the lower surface of some foliose

lichens.

FRUTICOSE L I C H E N S

Lichens with an erect or hanging growth form. They appear shrubby, finger-like, strap-like or thread-like and consist of a series of branching and non-branching stems.

1. Cladia aggregata (Fig. 5a) Of variable tufted or shrubby form; characterised by densely

branching, often tangled, sparsely fissured stems; straw-coloured and brittle when dry, yellow-green and flaccid when wet; small black apothecia on tips of some branches. The most common soil-inhabiting lichen of the Auckland area; particularly abundant beneath teatree scrub and on clay banks; also on rotting logs, tree stumps and damp sides of rocks.

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Another lichen found on soil beneath teatree scrub in the Auckland area is the distinctive, white, coral lichen Cladia retipora.

Cladonia This large genus, with over 40 species recorded from the Auckland

region, is usually found on soil. It begins growing as a primary thallus of squamules, from which develop simple or branched, erect, hollow stems. If fertile, the stems carry apothecia (brown or red) on their apices. Mature specimens of several species (e. g. C. capitellata C. leptoclada) usually lack squamules. Three of the most common and distinctive species in the area are:

2. Cladonia capitellata (Fig. 5b) Simple or sparsely branched stems, crowded together; infertile; 3-5 cm

high.

3. Cladonia chlorophaea (Fig. 5c) A pixie-cup lichen with unbranched stems and a large, sorediate,

trumpet-like cup on each.

4. Cladonia leptoclada (Fig. Ia) "reindeer lichen" Densely branched with slender, entangled, sharply pointed branches.

Used as trees in model railways.

Ramalina A n erect or pendulous lichen with flattened stems, usually sparsely

branched, and with flat, disc-like, lecanorine apothecia on the margins or surface of the stems. Three species are often encountered in the Auckland area: R. myrioclada (very narrow stems, terete in part; on coastal rocks and trees); R. peruviana (stubby with sorediate stems); and the most common R. linearis:

5. Ramalina linearis (Fig. Ib) Extremely variable form, split into many artificial species in the past.

Stems may be long or short (2-10 cm length), narrow or broad (0. 2-2 cm wide), rigid and wrinkled or smooth and flaccid. In the city this is one of the commonest lichens on the branches of citrus and deciduous trees; also often found on native trees, wooden structures, rocks, tile roofs and brick chimneys.

6. Stereocaulon ramulosum (Fig. 5d) A n erect tufted lichen with solid stems (circular in cross-section)

covered in phyllocladia, and with occasional globular, wrinkled, purplish cephalodia; variable size (1. 5-20 cm high) with branched stems forming dense tufts or a loose, tall form, depending on the habitat; brown to

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black, globular, lecideine apothecia usually occur on the ends of main stems (Galloway 1980a). Found commonly on rocks or soil, often forming a dense cover over weathered rock in road-cuts. A second species occurring less commonly in the Auckland area is S. vesuvianum (short, simple or sparingly branched; on hard rocks).

7. Teloschistes chrysophthalmus (Fig. lc) A conspicuous, tufted lichen (1-3 cm tall), with pale orange to grey,

flattened stems (white or yellow-white undersides) and yellow-orange, disc-like, lecanorine apothecia with ciliate margins. Frequently seen in Auckland on the branches of citrus, apple, pear and deciduous ornamental trees.

8. Usnea spp. (Fig. Id) "old man's beard lichen" Short, erect, tufted, to long, pendulous lichens. Stems (circular in

cross-section) sparsely or copiously branched; straw-yellow to yellow-green or reddening; stout or slender; smooth, rough, sorediate or isidiate; each stem with a tough, central, internal cord. Lecideine apothecia terminal, but often absent. This large genus is not well studied and species differentiation is still problematical. In Auckland, Usnea commonly occurs on the bark of trees, on wooden fences and more rarely on tile roofs, brick chimneys and rocks.

FOLIOSE L I C H E N S

Lichens with flat, leaf-like forms, smooth or wrinkled and often with intricately dissected lobes; loosely or firmly attached to the substrate by rhizines.

9. Dirinaria picta (Fig. le) Thallus subcircular (4-8 cm diameter), whitish-grey (when dry), lower

surface black, lacking rhizines, closely attached to substrate; narrow, radiating lobes (1-1. 5 mm broad), contiguous at thallus centre, more or less discrete at periphery with rounded or spathulate ends. Surface covered with numerous, discrete, light grey, globose soralia (1 mm diameter); black, lecanorine apothecia. One of the most common lichens in Auckland, occurring abundantly on the bark of most kinds of tree, as well as on stone walls, brick chimneys and fences, wooden fences and tile roofs.

Heterodermia Microscopical thin-sectioning is required to definitely recognise this

genus, but it is generally recognised by its subcircular, prostrate growth form (3-8 cm diameter), with narrow lobes (1-4 mm broad), whitish-grey to olive-grey upper surface and white lower surface that often lacks a

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lower cortex; attached to substrate by black rhizines. The two most common species in Auckland are:

10. Heterodermia dendritica (Fig. 5e) Narrow (1-2 mm broad), light olive-grey, convex lobes, lacking soralia.

Usually occurs on basalt and greywacke rocks.

11. Heterodermia pseudospeciosa (Fig. 5f) Narrow (1-2 mm broad), whitish-mineral grey, flat lobes with common

crescent-shaped, powdery soralia on lobe ends and margins. Often seen on bark, hard rock, brick chimneys and tile roofs.

12. Leptogium spp. (Fig. If) A large genus with many New Zealand species, requiring close

examination for discrimination. Leptogium are small, dark, foliose lichens with a lead-grey, slaty-blue or brownish, shining, upper surface. They swell up and become gelatinous when wet. The closely-related genus Collema is distinguished from Leptogium by its black colour and tendency to swell even more when wet. Leptogium and Collema are generally found on bark or occasionally rock in fairly dark habitats, such as in a grove of evergreen trees.

13. Neofuscelia spp. (Fig. lg) A recently established genus for the "brown Parmelias", recognised

by its olive-brown or blackish-brown upper surface. Foliose thallus (up to 10 cm diameter) composed of lobes of variable shape and size; lower surface usually black or dark brown, occasionally light brown; attached to substrate by rhizines. Neofuscelia seldom grows on wood and is often seen in Auckland on stone walls and tile roofs. The two species most frequently seen in the city are N. pulla (smooth to wrinkled upper surface, no isidia) and N verrucella (isidiate upper surface).

14. Pannaria spp. (Fig. 5g) Small, dark, foliose or squamulose lichens; usually grey in colour and

subcircular in outline; small, reddish-brown, lecanorine apothecia with crenulate thalline margins. Pannaria is easily distinguished from similarly-coloured Collema and Leptogium in that it does not swell to become gelatinous when wet. Pannaria and its close relative Parmeliella are common forest lichens but are also sometimes present on tree bark in shady situations within the city. Several species are represented.

Parmotrema Large, broad-lobed (generally wider than 5 mm) Parmeliaceans with a

greenish-grey to whitish-grey upper surface. Lower surface usually black with simple rhizines and a characteristic brown, rhizine-free zone

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around the lobe margins. A dozen species are known in the Auckland area. The most common are P. cetratum (lacks soredia and isidia), P. crinitum (isidiate), P. perlatum (sorediate) and P. reticulatum (like P. perlatum but with upper surface finely reticulately cracked).

15. Parmotrema crinitum (Fig. 5h) Characterised by dense isidia on the central part of the upper surface;

larger isidia (up to 1 mm tall) are often branched and coral-like with black apical cilia; lobe margins ciliate. Found commonly on rock or bark in coastal locations.

16. Parmotrema perlatum (Fig. lh) Characterised by crescent-shaped or linear soralia on curled lobe

margins; soredia powdery and white; upper surface mineral grey and seldom cracked; lacks isidia. The most common Parmotrema in Auckland, it occurs on almost every lichen-inhabited substrate in the city. Together with P. reticulatum it is particularly common on the bark of most trees and also on brickwork, stone walls and tile roofs.

17. Peltigera dolichorhiza (Fig. 6a) A dark, blackish-green foliose lichen with broad lobes; lower surface

whitish, with prominent, dark, raised, branching veins with rhizines attached; flat, circular, black apothecia occur on the upper surface of some erect lobe tips. The most common Peltigera in New Zealand, it grows in damp locations usually on soil, mosses or rotten logs.

Pseudocyphellaria Large green or grey foliose lichens with a brown or buff undersurface

often covered in tomentum. If the thallus is ripped the medulla is seen to be pure white or bright yellow. Pseudocyphellaria is characterised by the presence of pseudocyphellae on the lower surface, whereas the closely related genus Sticta has cyphellae (Fig. 4).

Over 25 species of Pseudocyphellaria and Sticta are known in the Auckland region, but occur most commonly in mature teatree scrub or native forest. Several species are seen in Auckland city, mostly on bark in patches of bush or on coastal pohutukawas. The four most likely to be encountered are:

18. Pseudocyphellaria aurata (Fig. 2a) Brownish when dry, bright green when wet; yellow medulla; golden

yellow soredia on margins of lobes; black, lecanorine apothecia.

19. Pseudocyphellaria crocata (Fig. 6b) Dark brown when dry, dark grey when wet; white medulla; golden

yellow soredia on margins and surface of broad lobes. Mostly found on

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damp sides of basalt rocks.

20. Pseudocyphellaria faveolata (Fig. 6c) Light brown-green when dry, bright green when wet; white medulla;

lacks soredia and isidia; lobes long, narrow (2-10 mm wide) and dichotomously branched, with strongly wrinkled to dimpled surface; apothecia change from white to black as they mature.

21. Pseudocyphellaria flavicans (Fig. 6d) Light brown-green when dry, bright green when wet; yellow medulla;

lacks soredia; isidiate surface; lobe margins much dissected and squamulose, often exposing the bright yellow of the medulla.

22. Pseudoparmelia spp. (Fig. 2b) Medium-sized Parmeliaceans with a yellowish or greenish-grey upper

surface; lobes often black-rimmed and lacking cilia; unbranched rhizines occur over full width of black undersurface. Two greenish-yellow species with pustular, yellow soralia on their lobe surfaces, are commonly found in Auckland: P. caperata (broad lobes, 5-15 mm wide) usually occurs on the bark of introduced trees; P. soredians (narrow lobes, less than 5 mm wide) is often found on the bark of citrus and deciduous trees, on rock walls and tile roofs. 23. Psoroma spp. (Fig. 6e)

Yellowish, brownish or greenish, foliose lichens, generally with narrow, branching lobes (0. 5 - 2 mm wide) with bluntly rounded ends; some species have small squamules in the centre of the thallus; lecanorine apothecia commonly present, often crowded on the surface. At least 8 species are known from the Auckland region and several of these can be found on bark in patches of bush in the city.

24. Xanthoparmelia spp. (Fig. 2c) Yellow-green Parmeliaceans with fairly narrow lobes (1-5 mm wide)

lacking marginal cilia; lower surface black, brown or pale tan, with sparse rhizines (Galloway 1980b). Three species are common in Auckland: X. australasica (isidiate with black undersurface) occurs on rock and bark especially in coastal localities; X. scabrosa (isidiate with pale tan undersurface) is the most abundant lichen in the city, growing profusely on tarsealed roads, roadside curbs, rock walls, concrete structures, tile roofs, and less abundantly on bark and sometimes even on iron roofs and glass; X. furcata (narrow, dichotomously branched lobes; no isidia or soredia; pale brown undersurface) occurs on rock or soil, generally in coastal localities.

Xanthoria Bright yellow or orange foliose lichens. The two species most likely to

be seen in Auckland are:

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Fig. 5. Common fruticose (a-d) and folios* a. Cladia aggregata (1); c. Cladonia chlorophaea (3); e. Heterodermia dendritica (10); g. Pannaria sp. (14); Scales with 1 mm divisions, coin 17 mm

j (e-h) lichens of Auckland. b. Cladonia capitellata (2); d. Stereocaulon ramulosum (6); f. Heterodermia pseudospeciosa (11); h. Parmotrema crinitum (15).

diameter.

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25. Xanthoria elegans (Fig. 6f) Rosette-shaped thallus (up to 6 cm diameter), composed of narrow

gently convex lobes (less than 1 mm wide); thallus and lecanorine apothecia bright orange-red colour. A common lichen on coastal basalt and greywacke rocks but also present in the city on tile roofs and brickwork.

26. Xanthoria parietina (Fig. 2d) Rosette-shaped or spreading thallus (up to 10 cm diameter), composed

of flat lobes (1-3 mm wide), often with sinuous margins; lecanorine apothecia yellow-orange; thallus varying in colour from yellow-orange in exposed habitats to yellowish-green or greenish-grey in the shade. One of the commonest lichens in Auckland, it occurs on most substrates, especially brick chimneys, concrete structures and tile roofs.

CRUSTOSE L I C H E N S

Lichens that are tightly attached to, or immersed in the substrate and look like splashes of paint on stone or wood. They are often recognised as lichens by their apothecia scattered over the surface. Most genera and the majority of species require thin-sectioning of the fruiting bodies and microscopic examination of their structure and their spores for accurate identification.

27. Lecidea spp. (Fig. 2e) Crustose lichens with small, globular, lecideine apothecia. There are

numerous species in New Zealand, but they are poorly known. They are commonly seen in Auckland on bark (both smooth and rough), rock walls and sometimes tile roofs.

28. Lecanora spp. (Fig. 2f) Crustose lichens with circular, flat-topped or concave, lecanorine

apothecia (usually black or brown) with thalline margins the colour of the thallus. Several species are present in Auckland. Most occur on smooth bark or on rock.

29. Opegrapha spp. (Fig. 6g) Crustose lichens characterised by their small, black, elongate fruiting

bodies (called lirellae) that appear to be stuck on the surface of the thallus. Five species are known from the Auckland region - O. agelaeoides, O. diaphoriza, O. intertexta, O. spodopolia, O. stellata (Hayward 1977). Found commonly on bark, rock and sometimes wooden fences.

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Fig. 6. Common foliose (a-f) and crustose a. Peltigera dolichorhiza (17); c. Pseudocyphellaria faveolata (20); e. Psoroma sp. (23); g. Opegrapha agelaeoides (29); Scales with 1 mm divisions; coin 17 mm

(g-h) lichens of Auckland. b. Pseudocyphellaria crocata (19); d. Pseudocyphellaria flavicans i(21); f- Xanthoria elegans (25); h. Pertusaria sp. (30).

diameter.

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30. Pertusaria spp. (Fig. 6h) Lichens with a crustose thallus, usually white or dingy grey; fruiting

bodies immersed in surface warts, which are sometimes covered in soredia. Many species are present in New Zealand. Mostly found on bark and rarely on rock.

31. Phaeographis spp. (Fig. 2g) The most common genus of Graphidaceae in Auckland. The family is

characterised by elongate, usually dark coloured, fruiting bodies (lirellae), that are generally more submerged in the thallus than in Opegrapha and also have a better-developed, raised thalline margin. Nine species of Graphidaceae are known from the Auckland region -Graphina monospora, G. novaezelandiae, G. subvelata, Graphis elegans, G. librata, G. inquinata, Phaeographis australiensis, P. exaltata and P. inusta (Hayward 1977). Found commonly on tree bark, rarely on rock.

32. Thelotrema lepadinum (Fig. 2h) Dingy-yellow, crustose thallus; characterised by the presence on the

surface of numerous, crater-like, conical tubercles, which house the fruiting bodies. Commonly occurs in Auckland on bark and very rarely on rock.

S O M E U S E F U L R E F E R E N C E S

Galloway, D. J . 1980a: The lichen genera Argopsis and Stereocaulon in New Zealand. Botanical Notiser 133: 261-279.

Galloway, D. J . 1980b: Xanthoparmelia and Chondropsis (Lichenes) in New Zealand. New Zealand Journal of Botany 1& 525-552.

Galloway, D. J . in prep. "Flora of New Zealand. Lichens. " Government Printer, Wellington.

Degelius, G. 1974: The lichen genus Collema with special reference to the extra-European species. Symbolae Botanicae Upsaliensis XX: 2, 215p.

Hale, M . E . 1979: "How to know the lichens. " 2nd Edition, W. C. Brown Co., Iowa. 246 p. Hayward, G. C. 1977: Taxonomy of the lichen families Graphidaceae and Opegraphaceae in

New Zealand. New Zealand Journal of Botany 15: 565-584. Martin, W. & Child, J . 1972: "New Zealand Lichens. " A . H . & A . W. Reed, Wellington.

193 p. Rogers, R. W. 1981: "The Genera of Australian Lichens. " University of Queensland Press,

St. Lucia. 124 p.

GEOLOGY

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